In a wireless network containing a network controller (e.g., an access point (AP)) and multiple mobile devices (e.g., STAs), sometimes a pair of STAs will establish a direct communications link with each other (i.e., communication between those two STAs does not have to be routed through the AP). If these two STAs have the capability for directional communication, that link may also be a directional link. However, even though their link is directional, their communication with each other may still cause interference with other devices, either due to the position of those other devices or because of the side lobes of the directional transmissions. Steps may need to be taken to see if such communication interferes with communication by other directional pairs, to determine if spatial reuse can take place (i.e., each pair communicates over their respective directional links at the same time). Traditionally, such spatial reuse takes place during Service Periods (SP), in which STA communication is scheduled by the AP and therefore the AP can avoid potential interference situations. But there is an increasing need for such spatial reuse to take place during Contention Based Access Periods (CBAPs), which are periods for unscheduled first-come first-serve access to the medium.
Wherever possible, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts.